The present invention relates to a drinking water filter for attachment to a faucet and, more particularly, to a filter apparatus which includes a filter cartridge that is quickly and simply removable.
Small drinking water filters which are directly attachable to a conventional faucet are well known in the art. These filters typically include an external housing including an integral means for attaching the housing to the faucet and a replaceable filter cartridge which is inserted in the housing and may be periodically replaced. The filter media contained in the replaceable cartridge is typically activated carbon which is effective in removing suspended materials, as well as certain undesirable tastes and/or odors from drinking water. Other types of filter media may also be used, such as for example an iron removal material. The faucet connection from the housing also typically includes a manually operable valve allowing the user to selectively allow tap water from the faucet to be directed straight through the connection without filtering or to divert the water from the faucet through the filter. U.S. Pat. Nos. 4,686,037, 4,172,796 and 3,853,761 are typical of prior art constructions.
All of the foregoing prior art filter constructions suffer from a number of deficiencies. The filter housing must typically be removed from the apparatus to expose the filter cartridge which is, in turn, removed and replaced as a separate element. In addition, other separate parts, such as O-rings, gaskets and the like, are also typically removed when the filter housing is opened and require careful replacement with the replacement cartridge. Disassembly of these units for filter cartridge replacement typically involves at least two and sometimes three sealed joints, each of which must be carefully resealed when the cartridge is changed and the housing is replaced. Seals that are intended to remain permanently in place in these prior art constructions are subject to deterioration and leakage over time. The filtered water discharge opening comprises a permanent part of the housing construction in prior art devices and is subject to deterioration and to a build up of deposits remaining in the filtered water. Finally, prior art cartridge filter devices, requiring removal of the outer housing, also inherently expose the interior of a large part of the filter construction to view by the user. The result is the exposure of often times very unsightly (though harmless) deposits left by the unfiltered tap water.
There is a need, therefore, for a cartridge filter for faucet attachment which overcomes the deficiencies noted in prior art devices and which is of simple construction, including an easily replaceable filter cartridge.